Measuring gauge



W. HUMPHREYS.

MEASURING GAUGE.

APPLICATION FILED DEC. 2 6, 1919.

tnuran stares earanr-oanca.

WILLIAM HUMPI-IREYS, FULLERTON, PENNSYLVANIA, ASSIGNOB T0 WIL-MORT MANUFACTURING COMPANY, OE CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

MEASURING GAUGE.

' Specicaton of Letters Patent.

rammen Jury ii, ieee.,

Application led December 26, 1919. Serial No. 347,554.

ing at Fullerton, in the county of Lehigh and State of Pennsylvania, have invented a certain new and useful Improvement 'in Measuring Gauges, of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawings, forming a part of this specication. j

My invention relates to an improved measuring gauge for measuring the thickness or diameter or other dimensions of various objects. More particularly, the present gauge is of the direct reading dial type adaptedto indicate directly the thickness or other linear dimension of the object being measured.

rJlhe present invention is primarily concerned with an improved manner of constructing gauges of this general type, and has particular reference to numerous structural features, designed to provide an aecurate, simple measuring gauge of compact, inexpensive construct-ion.

A secondary object of the invention is to provide an improved arrangement of indicating dial and associated measuring scales for permitting micrometric readings of the gauge, whereby very small linear dimensions may be measured accurately and quickly.

lln the accompanying drawings:

Figure 1 is a side elevational view of my improved gauge;

Figures 2 and 3 are different end views of the same;

Figure 4 is an enlarged fragmentary sectional view taken approximately on the line 4 4 ot Figure 3; t

Figure 5 is an enlarged sectional view taken on the line 5 5 of Figure 1;

Figure 6 is an enlarged isolated view of the cover plate showing the Vernier scale thereon, and the several scales on the indicating dial, the cover plate being partially broken away and Figure 7 is a detail sectional vview illustrating the detent lever for retaining the stem in its different measuring positions.

rIhe gauge is embodied in a frame member 1 which is formed with a U shaped eX- tension 2. At its end the extension 2 is formed with a squared head 3 in which is .mounted an anvil screw 4, this anvil screw constituting the stationary contact member, between which and the movable contact member the object to be measured is placed. The screw 4 provides an adjustment for Calibrating the gauge and is adapted to be locked in any position by the lock nut 5. The movable Contact member for engaging the object to be measured consists of a cylindrical stem or plunger 6, which extends through guide openings in the main portion of the frame 1. The other end of the stem 6 projects out from the end of the trame 1 as indicated at 6, and it will be apparent that the two contact members can be made to approach each other for engaging the object 'to be measured by simply depressing the end of the stem 6. Where it isdesirable to have the device mounted stationary for facility of operation, I contemplate mounting the gauge as an entirety, either permanently or removably, on as tationary bracket, or mounting only the large portion of the frame 1, together with the stem 6, on the bracket, with the stem 6 cooperating with a stationary gauging Contact on the bracket.

The frame member 1, which preferably consists of a die casting, is formed with a cylindrical housing portion 7, which defines a circular recess or cavity 8 for receiving the Ainsertion of the toothed rack 14, which is carried by the stem 6. The outer end of the slot 13 is closed oit by a small stop plate 14, which, as clearly shown in Figure 4 is fastened to the end of the housing 7 by a single f screw 15, being securely held in place by an indentation or punching 16 which sets into the slot 13. The housing 7 adjacent the other hole 12 is similarly slotted or recessed as indicated at 17 to permit full longitudinal movement of thetoothed rack 14.

lThis rack 14 consists of a'toothed bar which is set into a slot 18 milled in the cylindrical body of the stem `6, the rack being rigidly held in place by punching or crimping the sides of the slot into rigid engagement with the rack. rlhe teeth of the rack 14 mesh with a spur pinion 19, which is mounted on a shaft 21 journaled centrally in the circular recess 8. As clearly shown.

in Figure 5, the ends of the shaft 21 are reduced as indicated at 22 to bear in small jewel bearings 23 and 24. The steel jewel v23 isimounted in the rear wall 25 of the housing portion 7, and the other slightly j shorter jewel 24 is mounted in a cover plate 26, which closes oif the open front of the housing portion 7. The shaft ends 22 are supported in closed end bearing pockets in the steel jewel, which are immune to the entrance of dust and dirt. 1 Both steel jewels 'are provided with exterior rounded heads held by screws v31-31.

27, which retain the jewels against inward displacement and also nicely finish off the outer appearance of the gauge. These steel jewels are preferably held in place by a force t, i. e. for eXamp-le bycrowding the metal around the jewel shank. It will be seen that byemploying the present form of jewel bearings, these bearings can be constructed of a' good quality ofvsultable steel and thereby insure eicient longwearing bearings, which could not be..obta1ned by forming the' bearings directly in the vbody of the device. lThis construction of jewel bearings effectually excludes the dustfrom the interior of the housing, and furthermore renders easythe renewal of the bearings, if the same should be desired.

The circular cover plate -26 is set into a spur pinion 19, which meshes with the toothed rack14, is mounted on the other sidev of the collar 35, .and a guiding washer 36 is supported outside of the pinion 19. The

" measured is located inaccessibly or in the dial 9 and pinion 19, together with the guide washer 3 6 are all rigidly pinned to the collar 35 by small pins 37, the -ends of which are headed to prevent, displacement. It

`will be-noted that thecollar 35 and guide washer 36 embrace the vsides of the teeth on the pinion 19'so as to prevent the accidental unmeshing of the'teeth on the rack 14, 'which might otherwise result from rotation of thev stem 6. Thel stem 6 is impelledgoutwardly so as to normall maintain the gauging contacts separated y means of .a spiralA springv 38 which 1s disposed -adjacentsthe rear housing wall 25. he innerv end ofthe spring 1s secured-in ahole in the shaft '21, 4as indicated at 39, and the outer end encircles the vreduced end of a stud. 41 formed integrally with the wall 25 from which` the'spring is.

prevented from accidentally disengaging by a screw 42. The spring l38 is preferably arranged so that the depression of the v'stem 6 coils the spring. In assembling the gauge this spring is placed under an initial expansion' tension so that the teethV of the pinion 19K/will always have the same correspending tooth lfaces in engagement with the tooth faces of the rack teeth. This relation eliminates all back lash and play between the toothed members, which might otherwise result in inaccurate readings.

The pinion 19 is preferably designed'with l a pitch circle of exactly one inch in circumference, so that a linear gauging motion of the stem equal to one inch will result in one entire revolution of the dial 9, whereby the dial can be divided up directly into the fractional parts of the inch. The dial 9 is marked oli' with two independent scales 45 and 46, the scale 46 being readable in the vdial ywindow 34. The scale 45 is subdivided into a plurality of minor scales beginning from the innermost scale, which is scaled into 8ths and, being graduated outwardly therefrom to the outermost scale which is scaled into 64ths. Small index pointers 47 and 48, formed in the beveled margins of the dial window 33, cooperate with these several scales for reading the same. The

,outer scale 46 is graduated intov hundredths on the Vernier are marked oli' to correspond to nine of the scale divisions of the hundredths scale 46. This particular numerical relation may of course be modified if d'esired.` The manner of using the Vernier willy be apparent to those skilled in the art.

It frequently arises that the object to be v dark, so that the reading of the dial with the gauging contacts in engagement with the object is inconvenient.l To obviate this objection I have provided an improved deject for reading in a more convenient position or ina better light. This detent lever is mounted in a slot 53 inthe frame 1, being pivoted on a short pivot pin 54, which 'is setl .into a drill hole, intersecting the slot. 53 Y (F1gure7). 'The detent lever comprises a clamplng portion 55which is, adapted vo be@ against thefsdeof the s'tem. Thisiao clamping portion may be provided with any preferred construction of frictional face for more efiiciently clamping'the stemV 6, if desired; The lever is held in firm frictional engagement with the stem by a compression spring 56 which is set into a cup-shaped depression in the bottom of the slot `53. The compression strength of vthis spring does not appreciably hinder the depressing of the stem in performing a measurement, but .it is ample to rigidly hold the stem-in its measuringposition after removal of the gauge from the object. permit return of the stem to normal position by simply depressing the projecting tail end of the detent lever. Y

Where several scales are desirable, such as separate scales for different systems of measurement or the like, l contemplate using two dials, the other dial being disposed adjacent the rear wall 25 of the housing and being readable through dial openings in this wall. rl`he instrument may also be employed with similar scales on both sides for the sake of greater convenience.

l claim:

l. ln a' measuring gauge the combination of a frame member having an extension supporting an adjustable contact screw, lsaid frame member comprising an open housing for enclosing an indicating dial, a gauging stem slidable in said vhousing and adapted to cooperate with said contact screw, acover plate for closing said housing, a shaft in said housing for supporting said' dial, and jewel bearings mounted in said housing and in said cover plate for pivotally supporting. said shaft, said jewel bearings comprising shank portions pressed in-to rigid setting in openings in said housing and said coser plate and having heads bearing against said housing and said cover plate. v

C2. ln a measuring gauge, the combination of a frame member having a U shaped eX- tension supporting an adjustable stationary gauging contact, said frame member comprislng an open housing, a. stem longitudinally slidable in said housing and adapted to cooperate with said gauging contact, an indicating'dial in said housing, a cover plate for closing sai-d housing, a shaft for supporting said indicating dial, a. pinion on said `shaft meshing with a rack on said stem, and metallic jewel bearings mountedv in said housing and in said cover plate for pivotally supporting said shaft, said jewel bearings being composed of harder bearingmetal than said frame member and comprising shank portions pressed int'o rigidl setting in'openings in said housing and saidl cover plate, said shank 'portions having heads engaging on lthe outer walls of said yhousing and Said cover plate and .having bearing recesses for receiving the ends of said shaft.

3. ln a linear measuring gaugefajframe rlhe detent lever is released tol member formed with a circular recess therein, a stem slidable through said frame member and having a rack mounted thereon, a shaft journaled in said recess, a rotatable indicating dial mounted on said shaft, a pinion on said shaft meshing with said rack supported by said stem, said frame member having a slot for permitting the insertion of said stem and rack into said circular recess, and a stop plate for closing said slot.

j 4. ln a linear measuring gauge, av frame member comprising la housing enclosing a rotatable indicating dial, a gauging stem slidable through said housing, said gauging stem comprising a rack adapted to rotate said dial, said housing having an opening therein for permitting the projection of said stem,

said housing having a slot extending from l said opening for permitting the entrance of said rack into said housing and a stop plate mounted on said housing for closing said circular openings to permit sliding motion of said stem, said housing having a slot formed co-extensive with one of said openings for permitting the insertion of said rack bar along with the stem intorsaid housing, a stop plate closing the outer end of said. slot, a screw for mounting said stop plate on said housing and a projection on said stop plate lying in said slot for holding said plate in proper position against said housing.

6. In a. linear measuring gauge, a frame member comprising a housing adapted 'to enclose a rotatable indicating dial, a stem slidable in said housing and having afrack mounted thereon, a shaft journaled in said.

nation of a frame member having an eXtension supporting a stationary gauging contact, said frame member comprising an open housing adapted to enclose a rotatable indicating dial, said dial having a plurality of measuring scales, a gauging stem reciprocablyV mounted in said housing andadapted to cooperate with said stationary gauging contact, a cover plate for closing said housing, said cover plate having a plurality of dial windows, a shaft for supporting said indicating'dial, metallic jewel Vbearings mounted in said cover plate and'n the rear wall of said housing forpivotally supporting said shaft, said shaft comprising reduced bearing ends engaging in said jewel bearings, said shaft i tending to said collar also comprising anenlargedfcollar portion, said indicating dial being mounted on one side of said collar portion and a rspur pinion mounted on the other side thereof, pins exortion for securing said dial and said pinion thereto, a spiral spring having its ends secured to said shaft and to said housing, and a rack depending from said stem. and meshing with said pinion.

8. In a linear measuring,r gauge, a lframe member having'an extenslon supporting a stationary gauging contact, said frame member comprising a housing adapted to enclose a rotatable indicating dial, a stem slidably mounted in'said housingand adapted tocooperate With said stationary gauging contact, a cover late closing said housing, a, shaft 'journale between said cover plate and said housing, said shaft supporting'said indicating dial, a. pinion on said shaftA meshing with a rack carried by. said stem, a plurality of concentric `scales on saidl dia-l of various degrees of gredation, dial window means for exposing the several scales on said dial, and a stationary Vernier scale of short angular dimension formed along one margin of said Window means and adapted to cooperate with one of said scales. i a

In Witness whereof, I hereunto subscribe my name this 29 day of November, 1919.

WILLIAM HUMPHREYS. 

